1. Field of the Invention
This invention relates to a reproduction apparatus and a reproduction method by which, from a recording medium on which main data, main management data to be used for management of recorded positions of the main data, sub data for modifying the main data and sub management data to be used for management of recorded positions of the sub data are recorded, the sub data are reproduced based on the sub management data in synchronism with the main data.
2. Description of the Related Art
As a recording apparatus and a reproduction apparatus which can record and reproduce music and so forth, a recording apparatus and a reproduction apparatus are known on which a magneto-optical disc, a magnetic tape or the like on which an audio signal is recorded as a digital signal is used as a recording medium.
In a recording and reproduction system in which a magneto-optical disc known as mini disc (Trade Mark) is used, a user not only can record and reproduce audio data of tunes and so forth as programs, but also can record a title of the disc, that is, a disc name, and titles, that is, track names, of the programs such as tunes recorded on the disc as character information on the disc. For example, upon reproduction, the disc title, the titles of the tunes, the names of artists and so forth can be displayed on a display section of a reproduction apparatus.
It is to be noted that, in the present specification, the term "program" is used to signify a unit of audio data or the like such as a tune as main data recorded on a disc. For Example, audio data for one tune make one program. Also the term "track" is used in the same significance as the "program".
A mini disc system in which a mini disc is used as a recording medium has been proposed by the Assignee of the present invention wherein a recording region into which sub data incidental to audio data as main data can be recorded is provided separately from a recording region into which the main data are recorded on a mini disc such that still picture data and character data can be recorded as the sub data. It is to be noted that the character data in the present specification include also data of symbols, marks and so forth.
For example, also a conventional mini disc system different from the mini disc system described above can record character information such as a disc name and a track name. Such character information is recorded in a corresponding relationship to each program in the U-TOC (User Table Of Contents) of a mini disc. However, since the U-TOC itself does not have a very large capacity, it merely allows recording of characters of titles and so forth.
In contrast, where a recording region for sub data is provided on a mini disc as described above, it can be realized readily to record not only character information but also video data which do not require a very large capacity such as, for example, a still picture.
As a form of utilization of sub data where a mini disc system is so configured as to record sub data such as images and character information in addition to main data onto a mini disc, it seems a possible idea, for example, to reproduce and output sub data corresponding to main data at a required timing synchronized with the reproduction time of the main data.
More particularly, for example, if it is assumed that a program of main data as a tune having a playing time of 2 minutes and two still picture files Picture #1 and #2 as sub data corresponding to the program are recorded on a disc, then the still picture file Picture #1 is displayed in synchronism for one minute of the former half of the 2-minute period within which reproduction of the program is performed, and the still picture file Picture #2 is displayed for one minute of the latter half.
The configuration which allows such synchronous reproduction not only allows enjoyment of a program reproduced as sound but allows a different manner of enjoyment such as to enjoy a still picture or characters displayed in accordance with a progress of the program being reproduced.
Conventionally, a mini disc system has a function of searching, for example, audio data as main data in a unit of a program in response to an operation of a user. In other words, by performing a search operation, a user can search for the head of a desired program and start reproduction of the program beginning with the head.
Here, if the configuration wherein a data file as sub data is reproduced or outputted in synchronism with the main data as described above is adopted, then the following search function can be provided to the mini disc system in addition to the search function by which the main data are searched in a unit of a program as described above.
In particular, a search function by which a search is performed with reference to sub data reproduced in synchronism with main data is provided. For example, the user designates, as an operation for the search, a desired still picture file or character information file from among files of sub data whose reproduction outputting times are prescribed with respect to programs, that is, main data. By the operation, the designated file of sub data is displayed, and audio reproduction of the main data in a section reproduced in synchronism with the thus displayed file of sub data is started.
Where the search function with reference to sub data just described is provided, for example, the user searches and quickly observes particular desired sub data files in the form of still picture files or character information files in an order of the reproduction time of the main data. The user can thus enjoy sound in the reproduction section of the main data synchronized with a sub data file being displayed. Reversely speaking, it is possible to confirm in what reproduction section of programs of main data what sub data file is set in a corresponding relationship so as to be reproduced in synchronism with each other. This preferentially augments the convenience of use of the mini disc system as much.